The present invention relates to pervaginal sling procedures using bone anchors.
Urinary stress incontinence, i.e., the inability to control urination from the bladder, is a distressing problem for more than ten percent of elderly women as well as for many young women. Different theories exist to explain the pathology. In a normally anatomically positioned bladder, the proximal urethra and the bladder are in pressure continuity with the abdominal cavity, so that an increase in abdominal pressure is transmitted both to the bladder and to the proximal urethra, resulting in normal continence. However, particularly among elderly women, the bladder and the proximal urethra tend to descend from their normal or original anatomic positions such that the bladder neck and proximal urethra move away from the posterior wall of the pubic bone. When this occurs, the proximal urethra is no longer in pressure continuity with the abdominal cavity; therefore, an unintended increase in intra-abdominal pressure (e.g. by laughing or coughing results in an increase in intravesical pressure, but no change in the urethral closing pressure, thereby producing so-called stress incontinence. It also appears that as the bladder descends, the urethra becomes shorter and curved, so that its radial tonic muscle contraction is reduced, contributing to incontinence. Another pathology may arise from urethral sphincteric damage (type III incontinence).
Most of the surgical treatments for stress incontinence involve bladder neck suspension. One treatment is by an open surgical operation, involving an incision in the abdominal wall and/or anterior vaginal wall, to reposition and suspend the bladder and proximal urethra to their normal or original anatomic positions. This is done by suspension of the bladder neck and periurethral tissue to the posterior wall of the pubic bone. In another surgical procedure, the bladder neck is elevated by suspension of suture threads passing, with the aid of long needles, from both sides of the urethra and the bladder neck to the lower abdominal fascia or superior pubic bone ramus.
In prior U.S. patents and applications (e.g., the Related Applications referenced above, including U.S. Pat. No. 5,520,700, issued May 28, 1996, pending U.S. patent application Ser. No. 08/733,798, filed Oct. 18, 1996, and pending Israeli Patent Application Ser. No. 127978, filed Jan. 8, 1999 and entitled xe2x80x9cIncontinence Devicexe2x80x9d, the disclosures of which are hereby incorporated by reference), apparatus and methods are disclosed which allow treatment of urinary stress incontinence by a pervaginal procedure. As disclosed therein, an inserter device can be utilized for ejecting and implanting a bone anchor (e.g. a staple or a bone screw) through the vaginal tissue to enter the pubic bone. Further, a non-linear inserter device can be used to install a bone anchor by either injecting (in the case of a staple) or screwing the bone screw into the pubic bone, with or without vaginal incision. The suture thread that is secured to the bone anchor(s) (e.g staple(s) or bone screw(s)), can be used to suspend the bladder neck and the periurethral tissue to the posterior wall of the pubic bone. In addition, the suture thread can be used to perform a sling procedure in which a piece of material, such as abdominal fascia, fascia lata, cadaveric fascia or synthetic material, is positioned below the bladder neck and attached at both extremities to the pubic bone, by the threads. (In the classic sling operation, the sling material is attached to the abdominal fascia either directly or by means of threads).
It has been found, however, in stapler devices, and especially those that require high impact for bone implantation, that the ejection of the staple from the device causes the stapler to recoil. As is apparent from basic physics, the action of ejecting the staple from the stapler is associated with a reaction force which forces the inserter/stapler and the hand of the individual (the physician) implanting the same to move backwards. As a result, the physician must take this recoil into account and use force to firmly press the stapler against the pubic bone to ensure that the bone anchor is properly and effectively ejected and implanted. Anyone familiar with carpentry-type staple guns is familiar with this recoil. If pressure is not placed over the head end of the stapler, and the surface into which the staple is driven is hard (as in the case of bone), the staple will not be fully implanted, but, rather, the user""s hand will recoil. The medical stapler should also be held perpendicular to the bone surface. The stapler must be held in that position with the stapler held firmly during and through the ejection process so that the stapler does not shift its position as a result of the recoil. Otherwise, undue movement of the stapler because of recoil can result in a staple being ejected in an incorrect orientation, or incompletely ejected into the bone of the patient. This problem is especially apparent where the material into which the staple is ejected is bone and the physical confines of the space where the medical physician""s hands are working is limited, i.e., within a vagina.
Similarly, where the inserter is a screwdriver type and the anchor is a screw type anchor, unless a hole is pre-drilled in the insertion site, constant firm pressure must be applied through the axis of the anchor (perpendicular to the pubic bone) to assist the self-tapping property of the anchor to facilitate insertion during screwing. The medical screwdriver type inserter must, therefore, be held in the correct position relative to the patient""s anatomy through the insertion process.
A purpose of the present invention is to provide mechanical leverage, which facilitates a constant pressure at the insertion site to minimize the effect of this recoil, increasing the ease of use of an inserter device in a medical procedure (whether a pusher or impact type inserter, or a screw inserter), and increasing an inserter device""s effectiveness. This furthers the self-tapping property of the bone anchor, whether it be an impact type or screw type anchor. A screw type inserter device can be used for greater ease and effectiveness of use over an impact type device, particularly in a pervaginal medical procedure.
A further purpose of the present invention is to provide leverage in the per vaginal insertion of a bone anchor into the pubic bone. The present invention allows the physician to employ a pulling force perpendicularly against the pubic bone of the patient, and to conveniently do so with one hand. The leverage, degree of accuracy and ease of insertion are believed to be significantly enhanced by the present invention.
In one embodiment, the present invention relates to per vaginal bone screw or staple insertion, without first drilling a hole in the bone, by use of a non-linear or C-shaped inserter having a rotating intravaginal head for per vaginal injecting or screwing with or without vaginal wall incision. An additional purpose of the present invention is to provide a screw or staple type bone anchor and related device and procedures for per vaginal incisionless or minimal incision bladder neck suspension.
In a further embodiment, the invention relates to medical sling procedures. It is believed by some physicians that a sling procedure has better long term results of bladder neck suspension for type I, II, and III incontinence. Therefore, the invention relates, in a further embodiment, to medical sling procedures using bone anchors, either staples or screws, with or without suture, and preferably further using a non-linear anchor inserter.
Such sling procedures (or xe2x80x9csling operationsxe2x80x9d) are medical procedures in which a sling material is positioned below the bladder neck and/or the urethra to give support like a hammock. Sling procedures have been described in the art in such references as: Blavias J G, Jacobs B Z, Pubovaginal fascial sling for the treatment of complicated stress urinary incontinence, J. Urol. 145(6): 1214-8 (June 1991); McGuire E J, Lytton B, Pubovaginal sling procedure for stress incontinence J. Urol. 119(1): 82-4 (Jan. 1978); and, McGuire E J, Abdominal procedure for stress incontinence, Urol Clin. North Am., 12(2):285-90 May 1985); the disclosures of which are incorporated herein by reference.
In these relatively minimally invasive techniques (which have recently become more common), the bladder neck and/or urethra is supported by a sling, so that the urethra is partially compressed and/or has a support below it. Thus, during straining and/or bladder/uretheral descent, pressure is applied between the urethra and the sling, thereby closing its lumen.
Benderev et. al, in U.S. Pat. No. 5,836,314 and Brenneman et al, in PCT publication WO 98/19606, the disclosures of which is incorporated herein by reference, describe examples of procedures for treating incontinence. Two or more bone anchors are attached to the pubic bone, and each anchor is pre-threaded with a suture. Brenneman suggests that a sling be attached to the sutures and that the the sutures then be pulled tight and knotted, thereby urging the sling towards the pubic bone. Benderev suggests integrally molding one end of a suture with a xe2x80x9csuture supportxe2x80x9d, which suture support is provided to prevent damage to the urethra by the sutures.
An object of the present invention is to provide a stapler device which is particularly useful for fastening threaded staples to a bone for various medical purposes, particularly to treat urinary stress incontinence.
According to one embodiment of the present invention, there is provided a stapler device comprising: a handle manually grippable by a user, containing a drive mechanism and a trigger to activate the drive mechanism; a barrel fixed to the handle; a guide for holding a staple to be ejected; and an ejector driven by the drive mechanism, movable in the barrel for ejecting a staple out through an end of the guide; characterized in that the end of the guide is formed to accommodate a suture thread fixed to the staple.
In one described embodiment, the barrel is rigid for holding the guide in a fixed prescribed direction; and in a second described embodiment, it is flexible to allow pointing of the guide in a desired direction.
In a third described embodiment, the end of the guide is formed with a slot, or a pair of slots, for receiving the thread fixed to the staple; and in a fourth described embodiment, it is formed with a recess, or a pair of recesses, for receiving the thread fixed to the staple.
Such an anchoring device is particularly useful for treating women suffering from urinary stress incontinence caused by the descending of the bladder and the proximal urethra from their normal anatomical positions. Thus, the anchor may be ejected through the vaginal wall to enter the pubic bone, and the suture thread secured to the anchor may be used for attaching the bladder neck and the proximal urethra to the posterior wall of the pubic bone. Such an anchor device may also be used in other applications; for example, in medical operations for the fixation of a shoulder capsule in a person suffering from chronic shoulder dislocation.
The present invention also addresses the difficulties experienced in the prior art by providing a xe2x80x9cCxe2x80x9d, xe2x80x9cVxe2x80x9d or other non-linear shaped insertion device for use in medical applications, and especially, per vaginal insertions of anchors of any type into the pubic bone of a patient. The insertion device, which may be rigid or flexible, is positioned during use so that force may be applied through the axis of the anchor. The weight of a patient can contribute to the force applied by the physician to firmly press the device against the patient""s anatomy, so as to minimize the effects of the problems normally associated with recoil. The present device is directed both toward a stapler device for use to eject a staple type bone anchor, and toward a screw type bone anchor inserter. The inserters can be useful in other applications, as well, beyond those applications disclosed herein.
Accordingly, it is an object of the present invention to provide an insertion device which minimizes recoil during ejection of a bone anchor into bone.
It is further an object of the present invention to provide an insertion device which minimizes recoil during per vaginal insertion of a bone anchor into the pubic bone and otherwise allows constant pressure to be applied during the per vaginal insertion of self-tapping anchors into the pubic bone.
It is a further object of the present invention to provide a device which facilitates additional pressure to be applied to the insertion site beyond the direct pushing pressure applied by the physician in the case of a linear inserter held in place in the vagina by the physician""s hand. With the present non-linear inserter, the physician""s hand is used to pull the inserter against the resistive force of the pubic bone, thereby forcing the anchor tip to penetrate the bone cortex. It is far easier to insert a bone anchor, staple or screw with the hands external to the vagina and by use of the pulling force perpendicular to the bone surface.
It is further an object of the present invention to provide an inserter device for medical applications which improves the accuracy, effectiveness and ease of anchor insertions.
It is further an object of the present invention to utilize the physical pulling force on the inserter to further fixate the anchor tip penetration force perpendicular to the bone surface and in line with the physician pulling force.
It is further an object of the present invention to utilize at least a portion of the weight of a patient""s body to maintain a bone anchor or screw inserter in firm contact with the patient during insertion of a bone anchor or screw into the patient""s bone.
It is a further object of the present invention to use at least a portion of the weight of a patient as counter balancing leverage against the recoil of a bone anchor/staple/screw being inserted into the bone of a patient.
It is further an object of the present invention to provide improved procedures and inserter devices for inserting bone anchors, staples and/or screws in medical procedures.
It is further an object of the present invention to provide an improved bone anchor inserter for use in and to facilitate medical applications.
It is further an object of the present invention to provide improved bone anchors and bone anchor inserters.
It is further an object of the present invention to provide improved bone anchors and bone anchor inserters for treatment of female urinary stress incontinence and for other medical applications.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence including per vaginal bone anchor insertion into the pubic bone. These bone anchors are preferably either in the form of staples or screws. The bone anchor inserter has either a non-linear (e.g. a xe2x80x9cCxe2x80x9d or xe2x80x9cVxe2x80x9d shape) or a linear shape and is operated either by an impact or by a rotational movement to insert a staple or screw into the bone with or without vaginal wall incision.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence by per vaginal bone anchor insertion into the pubic bone.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence by per vaginal bone anchor insertion into the pubic bone and the use of a sling procedure.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence by the suspension of the bladder neck by pervaginal bone anchor insertion into the pubic bone and the use of a nonlinear inserter and a sling procedure.
It is further an object of the present invention to provide improved methods for treatment of urinary stress incontinence by per vaginal suspension of a sling from the pubic bone.
The invention also provides bone anchors, such as staples and screws, having suture thread secured thereto, for ejection by bone anchor insertion devices, including, but not limited to, those described herein, and for use in accordance with medical procedures.
Further features and advantages of the invention will be apparent in conjunction with the description and the drawings.